State-of-the-art call centers use an automatic call distributor (ACD) to distribute incoming calls to specific agents or other resources throughout the center. Traditional automatic call distributors hold queued calls according to a first-come, first-served policy until agents become available. From the call center's perspective, a long queue results in abandoned calls, repeat call attempts, and ensuing customer dissatisfaction. These and other performance characteristics have been widely researched and investigated, for example, by Michael A. Feinberg, Performance characteristics of automated call distribution systems, Global Telecommunications Conference, 1990, and Exhibition, “Communications: Connecting the Future”, GLOBECOM '90, IEEE. 1990, Vol. 1, pp. 415-419.
An improved concept is known in the art as virtual queuing. Known virtual queuing systems allow customers to be called back by the call center instead of waiting in an automatic call distribution queue. As an example, U.S. Pat. No. 5,627,884 describes a method wherein caller information is automatically taken from a caller on hold, the call disconnected, and finally returned at the time when the caller would have been serviced had the caller stayed on hold. The caller's number is verified and either DTMF or verbal extension information is used to reconnect the call.
US 2014/226809 describes a virtual queuing server connected to a call center and maintaining virtual queues and a telephone for enqueuing a user of the call center to the virtual queues via the virtual queuing server. Virtual queuing is described using both a smartphone app (one user interface) and using a telephone (second user interface).
Known methods provides users with little or no indication of the expected time the caller will spend on virtual hold. The user is unable to predict when to expect the envisaged call-back, in particular when disconnected from the call center.